Polyamide composition

ABSTRACT

The invention pertains to a filled polyamide composition [composition (C)] comprising: —from 35 to 80% wt of at least one polyhydric alcohol-modified polyamide, comprising an amount of polyhydric alcohol (PHA, herein after) residues chemically bonded at least to a part of the polyamide [polyamide (A)] of at least 0.1% wt (based on the total weight of polyamide (A)); —from 10 to 65% wt of at least one filler [filler (F)]; —from 1 to 10% wt of at least one impact modifying rubber [rubber (I)]; and —from 0.01 to 3% wt of at least one copper-containing stabilizer, with above % wt being referred to the total weight of composition (C).

CROSS-REFERENCE TO RELATED APPLICATION

This application is a U.S. national stage entry under 35 U.S.C. § 371 ofInternational Application No. PCT/EP2014/065672, filed Jul. 22, 2014,which claims priority to European Application No. EP 13306061.6 filed onJul. 23, 2013. The entire content of each of these applications ishereby incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to the field of polyamide compositionshaving improved long term high temperature aging characteristics.

BACKGROUND ART

Polyamides are synthetic polymers widely used for the manufacture ofdiverse shaped articles, including moulded and injected parts, which areoften proposed for high the electro-, electronic, and automotiveindustry.

In these fields of use, the moulded polyamide article during its normaluseful lifetime is in contact with a heat source which frequentlyattains and/or which attains for a longer period temperatures largelyexceeding 100° C. The heat source may be a heat producing device or aheated device or may be the surrounding environment wherein the mouldedarticle is placed. Examples of heated devices or heat generating devicesare engines, or elements thereof, and electronic devices such assemiconductors. For the automotive segment high-temperature-useapplication are regularly found in so-called under-the-hood orunder-the-bonnet applications, herein referred to as high temperatureautomotive applications. Therefore, the invention in particular relatesto polyamide suitable for the manufacture of moulded articles for use inthe electro-, electronic, and automotive industry.

Moulded articles for the electro, electronic and automotive industry andmoulding compositions based on polyamides generally have to comply witha complex property profile, including, for the compositions as moulded,good dimensional stability, high heat distortion temperature (HDT) andgood mechanical properties, such as a high tensile strength, tensilemodulus and fatigue. Polyamide materials generally tend to show adecrease in mechanical properties due to thermal degradation of thepolymer. This effect is called heat ageing. This effect can occur to anundesirable extent. In particular with polyamides as the thermoplasticpolymer, the deteriorating effect of exposure to high temperatures canbe very dramatic.

In attempts to improve heat aging characteristics, it has beenconventional practice to add heat stabilizers to polyamide compositions.The function of a heat stabilizer is to better retain the properties ofthe composition upon exposure of the moulded article to elevatedtemperature. When using a heat stabilizer, the useful lifetime of themoulded material can be extended significantly, depending on the type ofmaterial, use conditions and type and amount of heat stabilizer.Examples of heat stabilizers typically used in polyamides are organicstabilizers, like phenolic antioxidants and aromatic amines, and copper,either in the form of a copper salt in combination with potassium iodideor potassium bromide, or in the form of elementary copper, and metalpowders, in particular iron powders.

Existing technologies, while leading to improvements of long-term heataging resistance, are nevertheless insufficient for more demandingapplications, involving exposure to higher temperatures; in manyapplications, retention of mechanical properties after long-termexposure to temperatures as high as 160° C., or even 180-200° C. andhigher becomes a basic requisite. The number of specialty applications,requiring compositions with improved heat ageing properties is alsoincreasing.

On the other side, it is common practice to improve impact properties,and more particularly multiaxial impact properties, of polyamidecompounds, so that the same possess increase impact strength, display aductile behaviour under load, and, in the unfortunate event of fracture,cracks and weak points will ideally remain concentrated around thestressed area and not to propagate, through the addition of toughenersor impact modifiers. Nevertheless, because these additives are generallybased on alpha-olefins backbones, they may negatively affect thermalresistance and ageing properties.

The aim of the invention is therefore to provide impact resistancereinforced polyamide compositions, which have better heat ageingproperties than the known compositions, thereby providing for thepossibility to make moulded articles that can be used at highercontinuous use temperatures than the moulded articles prepared with theknown compositions and which possess outstanding impact strength.

Within this scenario, WO 2007/036929 (NILIT LTD) Apr. 5, 2007 discloses,notably, glass fiber reinforced polyamide compositions, wherein thepolyamide is modified by a polyhydric alcohol chemically bonded at leastto a part of the polyamide. This document is silent about heat agingproperties of said compositions.

Further, US 2010029819 (DU PONT) Feb. 4, 2010 teaches that glass fiberreinforced polyamide compositions comprising one or more polyamide, andone or more polyhydric alcohol (in amount of 0.25 to 15% wt), andoptionally a polymeric toughener deliver improved thermal resistance.

Still, WO 2012/140100 (RHODIA OPERATIONS) Oct. 18, 2012 is directed tothe use of polyhydric alcohols in polymerization of polyamides, so as tomanufacture polyamide modified by incorporation in the polymer chain ofsaid polyhydric alcohols, for achieving thermal stabilization of thepolyamide. Hence, it discloses polyamides modified by a polyhydricalcohol chemically bound to the polyamides, which can be formulated withfillers and impact modifiers.

The Applicant has now found that by the incorporation in reinforcedcompounds based on polyamides modified with polyhydric alcohols ofcertain amounts of impact modifying rubber and copper-containingstabilizer is effective in delivering outstanding synergetic heat agingstability effect, in particular delivering outstanding retention ofmechanical properties even after long term exposure to temperatures ashigh as 210° C., while simultaneously providing toughening effect.

SUMMARY OF INVENTION

The invention thus pertain to a filled polyamide composition[composition (C)] comprising:

-   -   from 35 to 80% wt of at least one polyhydric alcohol-modified        polyamide, comprising an amount of polyhydric alcohol (PHA,        herein after) residues chemically bonded at least to a part of        the polyamide [polyamide (A)] of at least 0.1% wt (based on the        total weight of polyamide (A));    -   from 10 to 65% wt of at least one filler [filler (F)];    -   from 1 to 10% wt of at least one impact modifying rubber [rubber        (I)]; and    -   from 0.01 to 3% wt of at least one copper-containing stabilizer,        with above % wt being referred to the total weight of        composition (C).

The Applicant has surprisingly found that the simultaneous incorporationof above detailed amounts of impact modifying rubber andcopper-containing stabilizer in a PHA-modified polyamide is effectivenot only in improving impact resistance, but also in unexpectedlydelivering outstanding synergetic heat aging stability, improving heataging performances at temperatures as high as 210° C., ensuringoutstanding retention of mechanical properties, with substantiallybetter performances over un-modified polyamides or PHA-modifiedpolyamide comprising only the impact modifying rubber or thecopper-containing stabilizer.

The Polyamide (A)

The inventive composition comprises at least one polyhydricalcohol-modified polyamide, comprising an amount of polyhydric alcohol(PHA, herein after) residues chemically bonded at least to a part of thepolyamide [polyamide (A)] of at least 0.1% wt (based on the total weightof polyamide (A)).

The expression “polyhydric alcohol” and “PHA” is used within the contextof the present invention for designating an organic compound containingthree or more hydroxyl groups in the molecule. The PHA can be analiphatic, cycloaliphatic, arylaliphatic or aromatic compound, and maycomprise one or more than one heteroatoms, including N, S, O, halogenand/or P, and can comprise additional functional groups (other thanhydroxyl groups) such as ether, amine, carboxylic acid, amide or estergroups.

According to preferred embodiments, the PHA will comply with formulaR—(OH)_(n)  (I)

wherein:

-   -   n is an integer of 3 to 8, and preferably 4 to 8; and    -   R is a C₁-C₃₆ hydrocarbon radical.

Generally, hydroxyl groups of the PHA are bound to aliphatic carbonatoms; in other terms, the PHA is generally not a phenol-type compound.

Further, in order to ensure appropriate reactivity of the hydroxylgroups of the PHA, it is generally preferred for said hydroxyl group ofnot being sterically hindered. To this aim, the carbon atoms in alphaposition to the aliphatic carbon bringing the hydroxyl group aregenerally free from sterically hindered substituents, and morespecifically free from branched aliphatic groups.

Compounds suitable for being used as PHA within the frame of the presentinvention are notably:

-   -   triols, in particularly selected from the group consisting of        glycerol, trimethylolpropane, trimethylolbutane,        2,3-di(2′-hydroxyethyl)-cyclohexan-1-ol, hexane-1,2,6-triol,        1,1,1-tris(hydroxymethyl)ethane,        3-(2′-hydroxyethoxy)propane-1,2-diol,        3-(2′-hydroxypropoxy)-propane-1,2-diol,        2-(2′-hydroxyethoxy)-hexane-1,2-diol, 6-(2′        hydroxypropoxy)-hexane-1,2-diol,        1,1,1-tris-[(2′-hydroxyethoxy)-methylethane,        1,1,1-tris-[(2′-hydroxypropoxy)-methyl-propane,        1,1,1-tris-(4′-hydroxyphenyl)ethane,        1,1,1-tris-(hydroxyphenyl)-propane,        1,1,5-tris-(hydroxyphenyl)-3-methylpentane, trimethylolpropane        ethoxylate, trimethylolpropane propoxylate,        tris(hydroxymethyl)aminomethane,        N-(2-Hydroxy-1,1-bis(hydroxymethyl)ethyl)glycine (also know as        tricine), and salts thereof;    -   tetraols, in particularly selected from the group consisting of        diglycerol, di(trimethylolpropane), pentaerythritol,        1,1,4-tris-(dihydroxyphenyl)-butane;    -   polyols comprising 5 hydroxyl groups, in particular triglycerol;    -   polyols comprising 6 hydroxyl groups, in particular        dipentaerythritol;    -   polyols comprising 8 hydroxyl groups, in particular        tripentaerythritol;    -   saccharide-type polyols, in particular selected from the group        consisting of cyclodextrine, D-mannose, glucose, galactose,        sucrose, fructose, arabinose, D-mannitol, D-sorbitol, D- or        L-arabitol, xylitol, iditol, talitol, altritol, gulitol,        erythrol, threitol, D-gulono-1,4-lactone.

PHA which have been found to provide particularly good results withinthe frame of the present invention are diglycerol, triglycerol,pentaerythritol, dipentaerythritol (DPE), tripentaerythritol (TPE) anddi(trimethylolpropane), with dipentaerythritol (DPE) andtripentaerythritol (TPE) being preferred, and dipentaerythritol (DPE)particularly preferred.

As said, the polyhydric alcohol-modified polyamide comprises polyhydricalcohol (PHA, herein after) residues chemically bonded at least to apart of the polyamide; the expression “bonded at least to a part of thepolyamide” is intended to mean that at least a fraction of polyamide (A)molecules will comprise said PHA residues, for example coupled by esterbonds, while other polyamide (A) molecules maybe free from saidchemically bonded PHA residues.

It is understood that one or more than one of the hydroxyl groups ofsaid PHA may participate in the bonding to the polyamide (A) molecules.When two, three, or more, hydroxyl groups of said PHA participate in thebonding, the polyamide (A) may possess a branched structure.

Polyamide (A) is capable of being obtained by addition of a polyhydricalcohol having at least three hydroxyl functional groups to apolymerization medium, prior to or at any stage of the polymerizationprocess.

It is nevertheless essential that the addition of the PHA is carried outbefore completion of the polycondensation reaction, so as to ensure thatat least one of the hydroxyl function of the PHA is reacted, henceensuring bonding of a PHA residue to the polyamide molecule.

More precisely, polyamide (A) is obtained by condensation reaction inthe presence of said at least one PHA of at least one mixture selectedfrom:

-   -   mixtures (M1) comprising at least a diacid [acid (DA)] (or        derivative thereof) and at least a diamine [amine (NN)] (or        derivatives thereof);    -   mixtures (M2) comprising at least a lactam [lactam (L)];    -   mixtures (M3) comprising at least an aminocarboxylic acid        [aminoacid (AN)]; and    -   combinations thereof.

The amount of PHA used in the polymerization is generally of from 0.15to 20% wt, preferably of 0.5 to 10% wt, more preferably of 1 to 5% wt,with respect to the total weight of the monomer mixture(s).

It is generally understood that the fraction of PHA which can be thusbound to the polyamide molecule is of at least 50% moles, preferably atleast 70% moles, even more preferably at least 80% moles, with respectto the total moles of PHA used.

As a consequence, the polyamide (A) will possess a content of chemicallybonded PHA residues of at least 0.1% wt, preferably of at least 0.5% wt,even more preferably at least 0.75% wt and of at most 10% wt, preferablyof at most 7% wt, even more preferably of at most 5% wt, with respect tothe weight of the polyamide (A).

Although the presence of free PHA in the polyamide (A) cannot beabsolutely excluded, it is understood that the polyamide (A) willcomprise, if any, non-chemically bonded PHA in an amount of less than 2%wt, preferably of less than 1.5% wt, more preferably of less than 1% wt,with respect to the weight of the polyamide (A).

Acid (DA) derivatives include notably salts, anhydride, esters and acidhalides, able to form amide groups; similarly, amine (NN) derivativesinclude notably salts thereof, equally able to form amide groups.

Said acid (DA) can be an aromatic dicarboxylic acid comprising tworeactive carboxylic acid groups [acid (AR)] or an aliphatic dicarboxylicacid comprising two reactive carboxylic acid groups [acid (AL)]. For thepurpose of the present invention, a dicarboxylic acid is considered as“aromatic” when it comprises one or more than one aromatic group.

Non limitative examples of acids (AR) are notably phthalic acids,including isophthalic acid (IA), and terephthalic acid (TA),2,5-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid,3,5-pyridinedicarboxylic acid, 2,2-bis(4-carboxyphenyl)propane,bis(4-carboxyphenyl)methane, 2,2-bis(4-carboxyphenyl)hexafluoropropane,2,2-bis(4-carboxyphenyl)ketone, 4,4′-bis(4-carboxyphenyl)sulfone,2,2-bis(3-carboxyphenyl)propane, bis(3-carboxyphenyl)methane,2,2-bis(3-carboxyphenyl)hexafluoropropane,2,2-bis(3-carboxyphenyl)ketone, bis(3-carboxyphenoxy)benzene,naphthalene dicarboxylic acids, including 2,6-naphthalene dicarboxylicacid, 2,7-naphthalene dicarboxylic acid, 1,4-naphthalene dicarboxylicacid, 2,3-naphthalene dicarboxylic acid, 1,8-naphthalene dicarboxylicacid.

Among acids (AL), mention can be notably made of oxalic acid(HOOC—COOH), malonic acid (HOOC—CH₂—COOH), succinic acid[HOOC—(CH₂)₂—COOH], glutaric acid [HOOC—(CH₂)₃—COOH],2,2-dimethyl-glutaric acid [HOOC—C(CH₃)₂—(CH₂)₂—COOH], adipic acid[HOOC—(CH₂)₄—COOH], 2,4,4-trimethyl-adipic acid[HOOC—CH(CH₃)—CH₂—C(CH₃)₂—CH₂—COOH], pimelic acid [HOOC—(CH₂)₅—COOH],suberic acid [HOOC—(CH₂)₆—COOH], azelaic acid [HOOC—(CH₂)₇—COOH],sebacic acid [HOOC—(CH₂)₈—COOH], undecanedioic acid [HOOC—(CH₂)₉—COOH],dodecandioic acid [HOOC—(CH₂)₁₀—COOH], tetradecandioic acid[HOOC—(CH₂)₁₁—COOH], octadecandioic acid [HOOC—(CH₂)₁₆—COOH].

Preferably, the acid (DA) used for the manufacture of the polyamide (A)will be an acid (AL), as above detailed, possibly in combination with aminor amount of an acid (AR), as above detailed.

The amine (NN) is generally selected from the group consisting ofaliphatic alkylene-diamine, aromatic diamines and mixtures thereof.

Said aliphatic alkylene-diamine are typically aliphatic alkylenediamines having 2 to18 carbon atoms.

Said aliphatic alkylene diamine is advantageously selected from thegroup consisting of 1,2-diaminoethane, 1,2-diaminopropane,propylene-1,3-diamine, 1,3-diaminobutane, 1,4-diaminobutane,1,5-diaminopentane, 1,5-diamino-2-methyl-pentane,1,4-diamino-1,1-dimethylbutane, 1,4-diamino-1-ethylbutane,1,4-diamino-1,2-dimethylbutane, 1,4-diamino-1,3-dimethylbutane,1,4-diamino-1,4-dimethylbutane, 1,4-diamino-2,3-dimethylbutane,1,2-diamino-1-butylethane, 1,6-diaminohexane, 1,7-diaminoheptane,1,8-diamino-octane, 1,6-diamino-2,5-dimethylhexane,1,6-diamino-2,4-dimethylhexane, 1,6-diamino-3,3-dimethylhexane,1,6-diamino-2,2-dimethylhexane, 1,9-diaminononane,1,6-diamino-2,2,4-trimethylhexane, 1,6-diamino-2,4,4-trimethylhexane,1,7-diamino-2,3-dimethylheptane, 1,7-diamino-2,4-dimethylheptane,1,7-diamino-2,5-dimethylheptane, 1,7-diamino-2,2-dimethylheptane,1,10-diaminodecane, 1.8-diamino-1,3-dimethyloctane,1,8-diamino-1,4-dimethyloctane, 1,8-diamino-2,4-dimethyloctane,1,8-diamino-3,4-dimethyloctane, 1,8-diamino-4,5-dimethyloctane,1,8-diamino-2,2-dimethyloctane, 1,8-diamino-3,3-dimethyloctane,1,8-diamino-4,4-dimethyloctane, 1,6-diamino-2,4-diethylhexane,1,9-diamino-5-methylnonane, 1,11-diaminoundecane, 1,12-diaminododecane,and 1,13-diaminotridecane.

The aliphatic alkylene diamine preferably comprises at least one diamineselected from the group consisting of 1,6-diaminohexane,1,8-diamino-octane, 1,10-diaminodecane, 1,12-diaminododecane andmixtures thereof. More preferably, the aliphatic alkylene diaminecomprises at least one diamine selected from the group consisting of1,6-diaminohexane, 1,10-diaminodecane and mixtures thereof.

The aromatic diamine is preferably selected from the group consisting ofmeta-phenylene diamine, meta-xylylene diamine and para-xylylene diamine.

Preferably, the amine (NN) used for the manufacture of the polyamide (A)will be an aliphatic alkylene diamine, as above detailed, possibly incombination with a minor amount of an aromatic diamine, as abovedetailed.

Preferred mixtures (M1) are:

-   -   mixtures of adipic acid and 1,6-diaminohexane;    -   mixtures of adipic acid, terephthalic acid and        1,6-diaminohexane;    -   mixtures of sebacic acid and 1,6-diaminohexane.

Lactam (L) suitable for use for the manufacture of polyamide (A) can beany of β-lactam or ε-caprolactam.

Preferred mixture (M2) comprises ε-caprolactam.

Aminoacid (AN) suitable for use for the manufacture of polyamide (A) canbe selected from the group consisting of 6-amino-hexanoic acid,9-aminononanoic acid, 10-aminodecanoic acid, 11-aminoundecanoic acid,12-aminododecanoic acid.

It is still within the scope of the invention the addition to any ofmixtures (M1), (M2), (M3) and their combination of one or more than onepolyfunctional acid/amine monomers comprising more than two carboxylicacid and amine groups, e.g. polycarboxylic acid having three or morecarboxylic acid groups, polyamines having three or more amine groups,polyfunctional diacid including two carboxylic groups and one or moreamine groups, polyfunctional diamine including two amine groups and oneor more carboxylic acid groups. Incorporation of said polyfunctionalacid/amine monomers generally lead to branched structures, star-like ortree-like, such as those notably described in WO 97/24388 (NYLTECHITALIA [IT]) Jul. 10, 1997 and in WO 99/64496 (NYLTECH ITALIA [IT];)Dec. 16, 1999.

It is also further understood that one or more than one end cappingagent [agent (M)] can be added to any of mixtures (M1), (M2), (M3), andtheir combinations for the manufacture of polyamide (A), without thisdeparting from the scope of the invention. The agent (M) is generallyselected from the group consisting of an acid comprising only onereactive carboxylic acid group [acid (MA)] and an amine comprising onlyone reactive amine group [agent (MN)].

Acid (MA) is preferably selected from the group consisting of aceticacid, propionic acid, butyric acid, valeric acid, caproic acid, caprylicacid, lauric acid, stearic acid, cyclohexanecarboxylic acid, benzoicacid, preferably from acetic acid and benzoic acid.

Amine (MN) is preferably selected from the group consisting ofmethylamine, ethylamine, butylamine, hexylamine, octylamine,benzylamine, aniline, toluidine.

The composition (C) will comprise at least 35% wt, preferably at least40% wt, more preferably at least 50% wt of polyamide (A) as abovedetailed, with respect to the total weight of the composition (C).Still, the composition (C) comprises at most 80% wt, preferably at most75% wt, even more preferably at most 70% wt of polyamide (A) as abovedetailed, with respect to the total weight of the composition (C).

The Filler (F)

The composition comprises from 10 to 65% wt of one or more than onefiller (F).

Said filler (F) can be any reinforcement agent, but it is preferablyselected from the group consisting of calcium carbonate, glass fibers,glass flakes, glass beads, carbon fibers, talc, mica, wollastonite,calcined clay, kaolin, diatomite, magnesium sulphate, magnesiumsilicate, barium sulphate, titanium dioxide, sodium aluminium carbonate,barium ferrite, potassium titanate.

The filler (F), from morphology perspective, can be hence selected fromfibrous fillers and particulate fillers.

Preferably, the filler is chosen from fibrous fillers. Among fibrousfillers, glass fibers are preferred; they include chopped strand A-, E-,C-, D-, S- and R-glass fibers. Glass fibers with circular andnon-circular cross sections can be used. The expression ‘glass fiberswith non-circula cross section’ is used herein according to its usualmeaning, that is to say it is intended to refer to glass fibers having across section having a major axis lying perpendicular to longitudinaldirection of the glass fiber and corresponding to the longest lineardistance in the cross-section, and a minor axis, corresponding to thelinear distance in cross-section in a direction perpendicular to themajor axis. The non-circular cross section of the fiber may have avariety of shapes including cocoon-type shape, a rectangual shape, anelliptical shape, a polygonal shape, an oblong shape, without this listbeing exhaustive. The ratio of the length of the major axis to the minoraxis is preferably between about 1.5:1 to about 6:1, more preferablybetween about 2:1 to about 5:1, still more preferably between about 3:1to about 4:1.

In preferred embodiments, glass fibers, and more particularly, circularcross-section glass fibers will be used as filler (F).

The composition (C) will comprise preferably at least 15% wt, morepreferably at least 20% wt of filler (F), as above detailed, withrespect to the total weight of the composition (C).

Still, the composition (C) comprises usually at most 60% wt, preferablyat most 55% wt, even more preferably at most 50% wt of filler (F), asabove detailed, with respect to the total weight of the composition (C).

Particularly good results have been obtained when the composition (C)comprised from about 10 to about 40% wt of filler (F), as abovedetailed, with respect to the total weight of the composition (C).

Rubber (I)

The composition (C) comprises from 1 to 10% wt of at least one impactmodifying rubber [rubber (I)].

Rubbers (I) suitable for use in the composition (C) generally compriseat least one functional group able to react with the polyamide (A), andmore particularly with amine or carboxylic acid end groups of thepolyamide (A) [functionalized rubber (IF)].

The functional group of the functionalized rubber (IF) is generallyselected from carboxylic acid groups and derivatives thereof (includingnotably salts and esters); epoxy groups; anhydride groups, oxazolinegroups, maleimide groups or mixture thereof.

The functionalized rubber (IF) maybe an oligomer or polymer compound,wherein the functional groups can be incorporated by copolymerizing afunctional monomer during polymerization of the impact modifier backboneor by grafting of a pre-formed polymer backbone.

Said functionalized rubbers (IF) generally comprise recurring unitsderived from at least one of the following monomers: ethylene; higheralpha olefins including propylene, butene, octene; dienes, includingbutadiene and isoprene; acrylates, styrene, acrylonitrile; (meth)acrylicacid and derivatives thereof, including esters; vinyl monomers,including vinyl acetate, and other vinyl esters. Other monomers maybeequally comprised in the structure of the functionalized rubber (IF).

The polymer backbone of the functionalized rubber (IF) will generally beselected from elastomeric backbones comprising polyethylenes andcopolymers thereof, e.g. ethylene-butene; ethylene-octene;polypropylenes and copolymers thereof; polybutenes; polyisoprenes;ethylene-propylene-rubbers (EPR); ethylene-propylene-diene monomerrubbers (EPDM); ethylene-acrylate rubbers; butadiene-acrylonitrilerubbers, ethylene-acrylic acid (EAA), ethylene-vinylacetate (EVA);acrylonitrile-butadiene-styrene rubbers (ABS), block copolymers styreneethylene butadiene styrene (SEBS); block copolymers styrene butadienestyrene (SBS); core-shell elastomers of methacrylate-butadiene-styrene(MBS) type, or mixture of one or more of the above.

It is understood that in case no functional group is comprised in saidpolymer backbone, the functionalized rubber (IF) will furtherincorporate, by copolymerization or grafting, residues from functionalmonomers including any of carboxylic acid groups and derivatives thereof(including notably salts and esters); epoxy groups; anhydride groups,oxazoline groups, maleimide groups or mixture thereof. It is furtherenvisioned that said functional monomers may be used for furthermodifying backbones which may already comprise a functional group.

Specific examples of functionalized rubbers (IF) are notably terpolymersof ethylene, acrylic ester and glycidyl methacrylate, copolymers ofethylene and butyl ester acrylate; copolymers of ethylene, butyl esteracrylate and glycidyl methacrylate; ethylene-maleic anhydridecopolymers; EPR grafted with maleic anhydride; styrene-maleimidecopolymers grafted with maleic anhydride; SEBS copolymers grafted withmaleic anhydride; styrene-acrylonitrile copolymers grafted with maleicanhydride; ABS copolymers grafted with maleic anhydride.

Functionalized rubbers (IF) which have been found particularly effectivewithin the frame of the present invention are ethylene amorphouscopolymers grafted with maleic anhydride.

The amount of said rubber (I) is preferably of at least 2% wt, morepreferably at least 3% wt, with respect to the total weight of thecomposition (C). Still, its amount is preferably of at most 8% wt, morepreferably at most 7% wt, even more preferably at most 6% wt, withrespect to the total weight of the composition (C).

The Copper-Containing Stabilizer

Copper-containing stabilizers useful in the practice of the inventionmay be characterized as comprising a copper compound and an alkali metalhalide. More particularly, the copper-containing stabilizer will consistessentially of a copper compound [compound (Cu)] selected from the groupconsisting of copper (I) oxide, copper (II) oxide, copper (I) salt, forexample cuprous acetate, cuprous stearate, a cuprous organic complexcompound such as copper acetylacetonate, a cuprous halide or the like;and an alkali metal halide [halide (M)]. Preferably, thecopper-containing stabilizer will consist essentially of a copper halideselected from copper iodide and copper bromide and the alkali metalhalide will preferably be selected from the iodides and bromides oflithium, sodium and potassium.

A particularly preferred combination is the combination of CuI and KI.

The copper-containing stabilizer will preferably comprise a copper (I)compound [compound (Cu)] and an alkali metal halide [halide (M)] at aweight ratio compound (Cu):halide (M) of 1:99 to 30:70, preferably 5:95to 20:80, more preferably 10:90 to 15:85. A weight ratio compound(Cu):halide (M) which has been found particularly effective is of about0.15 (i.e. corresponding to about 13:87).

The combined weight of compound (Cu) and halide (M), i.e. of thecopper-containing stabilizer, in the composition (C) will amount to fromabout 0.01 to about 3 wt %, preferably from about 0.02 to about 2.5% wt,more preferably from about 0.1 to about 1.5 wt %, based on the totalweight of composition (C).

The amount of the compound (Cu) in the copper-containing stabilizer willgenerally be sufficient to provide a level of from about 25 to about1000 ppm, preferably of about 50 to about 500 ppm, more preferably ofabout 75 to about 150 ppm of Copper in the composition (C).

Optional Co-Stabilizers (S)

The composition (C) may also comprise one or more than one heatstabilizer or anti-oxidant, hereby referred to as ‘co-stabilizer (S)’,different from the copper-containing stabilizer.

Co-stabilizers (S), when used in the composition (C) are generallyselected from the group consisting of hindered amine compounds, hinderedphenol compounds, and phosphorous compounds.

The expression “hindered amine compound” is used according to itscustomary meaning in this field and generally intended to denotederivatives of 2,2,6,6-tetramethyl piperidine well known in the art (seefor example: Plastics Additives Handbook, 5th ed., Hanser, 2001). Thehindered amine compound of the composition according to the presentinvention may either be of low or high molecular weight.

The hindered amine compounds of low molecular weight have typically amolecular weight of at most 900, preferably at most 800, more preferablyof at most 700, still more preferably at most 600 and most preferably ofat most 500 g/mol.

Examples of low molecular weight hindered amine compounds are listed inTable 1 below:

TABLE 1 Formula (a1) 

(a2) 

(a3) 

(a4) 

(a5) 

(a6) 

(a7) 

(a8) 

(a9) 

(a10)

(a11)

(a12)

Among those low molecular weight compounds, the hindered amine ispreferably selected from the group consisting of the ones correspondingto formula (a1), (a2), (a11) and (a12). More preferably, the hinderedamine is selected from the group consisting of the ones corresponding toformula (a1), (a2), and (a12). Still more preferably, the hindered amineis the one corresponding to formula (a2).

The hindered amine compounds of high molecular weight are typicallypolymeric and have typically a molecular weight of at least 1000,preferably at least 1100, more preferably of at least 1200, still morepreferably at least 1300 and most preferably of at least 1400 g/mol.

Examples of high molecular weight hindered amine compounds are listed inTable 2 below:

TABLE 2 Formula (b1)

(b2)

(b3)

(b4)

(b5)

(b6)

The “n” in the formulas (b1) to (b6) of Table 2 indicates the number ofrepeating units in the polymer and is usually an integral equal orgreater than 4.

Among those high molecular weight compounds, the hindered amine ispreferably selected from the group consisting of the ones correspondingto formula (b2) and (b5). More preferably, the high molecular weighthindered amine is the one corresponding to formula (b2).

If used, the hindered amine compound is typically present in an amountof advantageously at least 0.01 wt. %, more preferably at least 0.05 wt.%, still more preferably at least 0.1 wt. %, based on the total weightof the composition.

Similarly, when present, the hindered amine compound is also typicallypresent in an amount of advantageously at most 3.5 wt. %, preferably atmost 3 wt. %, more preferably at most 2.5 wt. %, still more preferablyat most 2.0 wt. %, even more preferably at most 0.8 wt. % and mostpreferably at most 0.6 wt. %, based on the total weight of thecomposition.

The expression “hindered phenol compound” is used according to itscustomary meaning in this field and generally intended to denotederivatives of ortho-substituted phenol, especially (but not limited to)di-tert-butyl-phenol derivatives, well known in the art

Examples of hindered phenol compounds are listed in Table 3 below:

TABLE 3 (d1) tetrakis(3-(3,5-di-tert-butyl-4- hydroxyphenyl)propionate),commercially available notably as Irganox ® 1010 stabilizer from BASF

(d2) Thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxy-phenyl)propionate], commercially available notably as Irganox ®1035 stabilizer from BASF

(d3) Octadecyl-3-(3,5-di-tert.butyl- 4-hydroxyphenyl)-propionate,commercially available notably as Irganox ® 1076 stabilizer from BASF

(d4) N,N′-hexane-1,6-diylbis(3- (3,5-di-tert.-butyl-4-hydroxyphenylpropionamide)), commercially available notably as Irganox ®1098 stabilizer from BASF

(d5) 1,3,5-Trimethyl-2,4,6-tris(3,5- di-tert-butyl-4-hydroxybenzyl)benzene, commercially available notably as Irganox ® 1330 stabilizerfrom BASF

(d6) Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4- hydroxy-,C7-C9 branched alkyl esters, commercially available notably as Irganox ®1135 stabilizer from BASF

(d7) Hexamethylene bis[3-(3,5-di- tert-butyl-4-hydroxyphenyl)propionate], commercially available notably as Irganox ® 259 stabilizerfrom BASF

(d8) Tris(3,5-di-tert-butyl-4- hydroxybenzyl) isocyanurate, commerciallyavailable notably as Irganox ® 3114 stabilizer from BASF

(d9) 2,6-di-tert-butyl-4-(4,6-bis (octylthio)-1,3,5-triazin-2-ylamino)phenol, commercially available notably as Irganox ® 565stabilizer from BASF

(d10) commercially available notably as Irganox ® 1425 stabilizer fromBASF

(d11) 2-Methyl-4,6-bis (octylsulfanylmethyl)phenol, commerciallyavailable notably as Irganox ® 1520 stabilizer from BASF

(d12) 2,4-Bis(dodecylthiomethyl)-6- methylphenol, commercially availablenotably as Irganox ® 1726 stabilizer from BASF

(d13) Triethylene glycol bis(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate, commercially available notably as Irganox ® 245stabilizer from BASF

A hindered phenol compound which has been found particularly effectivein the composition (C) isN,N′-hexane-1,6-diylbis(3-(3,5-di-tert.-butyl-4-hydroxyphenylpropionamide))of formula (d4), as above specified.

If used, the hindered phenol compound is typically present in an amountof advantageously at least 0.01 wt. %, more preferably at least 0.05 wt.%, still more preferably at least 0.1 wt. %, based on the total weightof the composition.

Similarly, when present, the hindered phenol compound is also typicallypresent in an amount of advantageously at most 3.5 wt. %, preferably atmost 3 wt. %, more preferably at most 2.5 wt. %, still more preferablyat most 2.0 wt. %, even more preferably at most 0.8 wt. % and mostpreferably at most 0.6 wt. %, based on the total weight of thecomposition.

The co-stabilizers (S) may be at least one phosphorous compound selectedfrom the group consisting of an alkali or alkali earth metalhypophosphites, phosphite esters, phosphonites and mixtures thereof.

Sodium and calcium hypophosphites are preferred alkali or alkali earthmetal hypophosphites.

A phosphite ester may be represented by the formula P(OR)₃, while aphosphonite may be represented by the formula P(OR)₂R, wherein each ofR, can be the same or different and are typically independently selectedfrom the group consisting of a C₁₋₂₀ alkyl, C₃₋₂₂ alkenyl, C₆₋₄₀cycloalkyl, C₇₋₄₀ cycloalkylene, aryl, alkaryl or arylalkyl moiety.

Examples of phosphite esters are listed in the Table 4 below:

TABLE 4 Formula (e1) 

(e2) 

(e3) 

(e4) 

(e5) 

(e6) 

(e7) 

(e8) 

(e9) 

(e10)

(e11)

(e12)

Examples of phosphonites are listed in the table 5 below:

TABLE 5 Formula Structure (f1)

(f2)

When used in the composition (C), the phosphorous compound is preferablypresent in an amount of at least 0.01 wt. %, more preferably at least0.05 wt. %, based on the total weight of the composition.

The phosphorous compound is also preferably present in an amount of atmost 1 wt. %, more preferably at most 0.5 wt. %, still more preferablyat most 0.25 wt. %, based on the total weight of the composition.

Other Ingredients

The composition (C) may also comprise other conventional additivescommonly used in the art, including lubricants, plasticizers, colorants,pigments, antistatic agents, flame-retardant agents, nucleating agents,catalysts, and the like.

Still, the composition (C) can comprise one or more other polymers,preferably polyamides different from polyamide (A). Mention can be madenotably of semi-crystalline or amorphous polyamides, such as aliphaticpolyamides, semi-aromatic polyamides, and more generally the polyamidesobtained by polycondensation between an aromatic or aliphatic saturateddiacid and an aliphatic saturated or aromatic primary diamine, a lactam,an amino-acid or a mixture of these different monomers.

Manufacture of the Composition (C)

The invention further pertains to a method of making the composition (C)as above detailed, said method comprising melt-blending the polyamide(A), the filler (F), the rubber (I), the copper-containing stabilizer,and of any other optional ingredient.

Any melt-blending method may be used for mixing polymeric ingredientsand non-polymeric ingredients of the present invention. For example,polymeric ingredients and non-polymeric ingredients may be fed into amelt mixer, such as single screw extruder or twin screw extruder,agitator, single screw or twin screw kneader, or Banbury mixer, and theaddition step may be addition of all ingredients at once or gradualaddition in batches. When the polymeric ingredient and non-polymericingredient are gradually added in batches, a part of the polymericingredients and/or non-polymeric ingredients is first added, and then ismelt-mixed with the remaining polymeric ingredients and non-polymericingredients that are subsequently added, until an adequately mixedcomposition is obtained. If a reinforcing filler presents a longphysical shape (for example, a long glass fiber), drawing extrusionmolding may be used to prepare a reinforced composition.

Use of the Composition (C)

The composition (C), as disclosed above, is useful in increasinglong-term thermal stability at high temperatures of molded or extrudedarticles made therefrom. The long-term heat stability of the articlescan be assessed by exposure (air oven ageing) of 4 mm thick test samplesat various test temperatures in an oven for various test periods oftime. The oven test temperatures for the composition disclosed hereininclude 210° C. and up to 3000 hours test periods. The test samples,after air oven ageing, are tested for tensile strength and elongation tobreak, according to ISO 527-2/1A test method; and compared withunexposed controls having identical composition and shape, that are asmolded. The comparison with the as molded controls provides theretention of tensile strength and/or retention of elongation to break,and thus the various compositions can be assessed as to long-term heatstability performance.

In various embodiments the composition (C) has a 210° C./2000 hoursretention of tensile strength of at least 50% and preferably at least60%, based upon comparison with as molded non-exposed controls.

In another aspect, the present invention relates a use of the abovedisclosed composition (C) for high temperature applications.

In yet another aspect, the present invention relates to a method formanufacturing an article by shaping the composition (C) of theinvention. Examples of articles are films or laminates, automotive partsor engine parts or electrical/electronics parts. By “shaping”, it ismeant any shaping technique, such as for example extrusion, injectionmoulding, thermoform moulding, compression moulding or blow moulding.Preferably, the article is shaped by injection moulding or blowmoulding.

The molded or extruded thermoplastic articles disclosed herein may haveapplication in many vehicular components that meet one or more of thefollowing requirements: high impact requirements; significant weightreduction (over conventional metals, for instance); resistance to hightemperature; resistance to oil environment; resistance to chemicalagents such as coolants; and noise reduction allowing more compact andintegrated design. Specific molded or extruded thermoplastic articlesare selected from the group consisting of charge air coolers (CAC);cylinder head covers (CHC); oil pans; engine cooling systems, includingthermostat and heater housings and coolant pumps; exhaust systemsincluding mufflers and housings for catalytic converters; air intakemanifolds (AIM); and timing chain belt front covers. As an illustrativeexample of desired mechanical resistance against long-term hightemperature exposure, a charge air cooler can be mentioned. A charge aircooler is a part of the radiator of a vehicle that improves enginecombustion efficiency. Charge air coolers reduce the charge airtemperature and increase the density of the air after compression in theturbocharger thus allowing more air to enter into the cylinders toimprove engine efficiency. Since the temperature of the incoming air canbe more than 200° C. when it enters the charge air cooler, it isrequired that this part be made out of a composition maintaining goodmechanical properties under high temperatures for an extended period oftime.

Should the disclosure of any patents, patent applications, andpublications which are incorporated herein by reference conflict withthe description of the present application to the extent that it mayrender a term unclear, the present description shall take precedence.

The present invention is further illustrated by the following examples.It should be understood that the following examples are for illustrationpurposes only, and are not used to limit the present invention thereto.

Analyses

Viscosity index (unit: mL/g) was determined in solution in formic acidaccording to ISO307 standard.

Carboxylic acid End-Groups (CEG) concentration and Amine End-Groups(AEG) concentration were determined by titration (unit: meq/kg).

Melting temperature (T_(m)) and enthalpy (ΔH_(m)), crystallizationtemperature (T_(c)) were determined by Differential Scanning Calorimetry(DSC), using a Perkin Elmer Pyris 1 at 10° C./min.

Free polyhydric alcohol content (unit: wt.-%) determination:

Free DPE or TPE content in polyamide polymers and compounds wasdetermined using an Agilent 1100 series HPLC (light scattering detector)with classical C18 column, calibrated with 5 different concentrations ofDPE or TPE in TriFluoroEthanol/water 1/10 wt/wt solvent, followingprocedure as below detailed.

About 2 g of polyamide-modified PHA pellets were solubilized in 30 g oftrifluoroethanol+1 g/L of LiCl mixture at room temperature, and stirringwas continued until all polyamide-modified PHA pellets were dissolved.Then 300 g of water were added dropwise (within about 30 min) whilemaintaining the mixture under stirring at room temperature, so as toensure precipitation of the polyamide polymer chains. For free DPEcontent concentration determination, the stirring was further maintainedduring 60 min at room temperature. For free TPE content concentrationdetermination, the solution was heated below 90° C. for 15 min so as toensure solubilization of free TPE.

A specimen of the solution so obtained was injected, after filtrationthrough a 0.45 μm filter, in the above mentioned HPLC instrument, andcontent was determined based on calibration curves.

Determination was repeated twice, and values reported are the average ofthe two measured values.

PREPARATIVE EXAMPLES—GENERAL POLYMERIZATION PROCEDURE

In a batch reactor were introduced the required amount of Nylon 66 salt(hexamethylene diammonium adipate), water and anti-foaming agentSilcolapse® 5020, in combination with appropriate amount of PHA and,when used, of additional monomers, and possibly of a hypophosphitecatalyst. The polyamide was synthesized according to a standard processfor the synthesis of PA 66, followed by a finishing step in conditionsspecified below. The polymer was then extruded under the shape of astrand, cooled in a cold water bath and pelletized to get pellets.

Ingredients and polymerization conditions are summarized in table 6herein below.

TABLE 6 Example CPE1 PE1 PE2 PE3 Nylon66 salt (kg) 80.0 92.56 92.5692.56 DPE(*) (kg) — 2.47 — 2.51 TPE(*) (kg) — 2.47 — Adipic acid (kg) —0.71 0.48 1.73 Water (kg) 72.8 84.2 84.2 89.0 NaH₂PO₂ (ppm P) — 20 20 —Anti-foaming agent (g) 5.5 6.4 6.4 6.4 Finishing temp. (° C.) 275 275275 275 Finishing pressure (bar) 1 0.5 0.5 1 Finishing time (min) 30 2212 37 IV (mL/g) 137.5 109.2 116.3 139.2 CEG (meq/kg) N.M. 70.3 77.7121.4 AEG (meq/kg) N.M. 54.7 62 35.4 Tm (° C.) 262 N.M. N.M. 255 ΔHm(J/g) 67 N.M. N.M. 55 Chemically bonded PHA — 2.2 2.26 2.75 content(wt.-%) Free PHA content (wt.-%) — 0.8 0.73 0.25 (*)DPE:dipentaerythritol; TPE: tripentaerythritol.

General Procedure for Extrusion of Compounds and High Heat Long TermAgeing Testing

Before extrusion, pellets of the polyamides were dried to decrease watercontent below 1500 ppm. The compositions were obtained by melt blendingof the selected ingredients in a WERNER&PLEIFEDER® ZSK 40 twin-screwextruder using the following parameters: 35 kg/hour, 280 rounds perminute, 8 heating zone set-points: 250, 255, 260, 260, 265, 270, 275,280° C. All ingredients were fed at the beginning of the extruder. Theextruded strand was cooled in a water bath, then pelletized and theobtained pellets were stored into sealed aluminium line bags to preventmoisture adsorption.

The polyamides manufactured as above specified were compounded withfollowing ingredients:

-   -   Stabamid® 26AE2 PA66, which is a polyamide 66 commercially        available from Solvay (IV=134 mL/g), having more carboxylic        acids than amino end groups;    -   Vetrotex OCV 983 Glass fibers from Owens Corning;    -   Lubricant ethylene-bis-stereamide;    -   Exxelor® VA1803 from ExxonMobil, which is an amorphous ethylene        copolymer functionalized with maleic anhydride by reactive        extrusion;    -   CuI and KI from AJAY® Europe;

The compositions were injection-molded using a DEMAG® 50T injectionmolding machine at 290° C. with a mold temperature of 80° C. to prepare4 mm thick ISO527 samples. Before ageing, initial mechanical properties(E-modulus, tensile strength (TS) at break and strain at break) weredetermined by tensile measurements according to ISO 527/1A at 23° C., asaverage values from 5 specimens.

The samples were heat aged in a re-circulating air oven (HeraeusTK62120) set at 210° C. At various heat ageing times (500 h, 1000 h and2000 h), the samples were removed from the oven, allowed to cool to roomtemperature and placed into sealed aluminium lined bags until ready fortesting. Mechanical properties were measured according to the sameprocedure as before ageing.

The retention of a mechanical property (tensile strength at break,E-modulus, strain at break) is expressed as the percentage of the ratioof the value of the mechanical property after a certain heat ageing timeat the temperature T and the value of the mechanical property beforeageing. For example, for a heat ageing time of 500 h at T, retention(TS) is expressed as percentage of TS(500 h,T)/TS(initial).

The ingredients and their reciprocal amounts in the compositions and themechanical properties of the samples before and after air oven ageingare reported in Tables below.

TABLE 8 CE1 CE2 CE3 CE4 E1 CE5 Ingredients PA 66 wt % 59.25 64.7 — — — —PE1 wt % — — 61 — 60.7 — PE2 wt % — — — 61 — — PE3 wt % — — — — — 64.1Glass fibers wt % 35 35 35 35 35 35 Lubricant wt % 0.3 — — — — 0.3 Blackwt % 0.3 — — — — 0.3 VA1803 wt % 4 — 4 4 4 — CuI/KI wt % 0.15/1   0.04/0.26 — —  0.04/0.26 0.04/0.26 Cu (ppm) 500 133 0 0 133 133Compounds properties Free PHA — — 0.49 N.M. N.M. N.M. content(wt.-%)^((#)) Bonded — — 1.38 N.M. N.M. N.M. PHA content (wt.-%)^((#))TM (MPa) 11570 11800 11700 11800 11900 11780 TS_(B) (MPa) 189 211 205206 208 212 TE_(B) (%) 2.73 3.1 2.9 3.1 2.8 2.8 Heat ageing at 210° C.TS_(B)/R_(500 h) N.M. 153/73 202/99 204/89 201/97 N.M. (MPa)/(%)TS_(B)/R_(1000 h) 116/62  108/51 171/84 162/79 173/83 155/74  (MPa)/(%)TS_(B)/R_(2000 h) 45/24 20/9  56/27  70/34 138/66 72/34 (MPa)/(%) TM(MPa): Tensile modulus; TS_(B) (MPa): Tensile strength at break; TE_(B)(%): Tensile strain (or elongation) at break; TS_(B)/R_(500 h): TS_(B)(MPa)/retention (%) after 210° C. 500 h; TS_(B)/R_(1000 h): TS_(B)(MPa)/retention (%) after 210° C. 1000 h; TS_(B)/R_(2000 h): TS_(B)(MPa)/retention (%) after 210° C. 2000 h. ^((#))PHA (bonded/free)content with respect to the overall composition weight

As the examples clearly demonstrated, only the combination ofcopper-containing stabilizer and rubber (I) in a PHA-modified polyamidehave enabled achieving retention up to more than 65% of mechanicalproperties after heat ageing at 210° C. for as long as 2000 h.

The invention claimed is:
 1. A filled polyamide composition comprising,based on the total weight of the composition: from 50 to 70% wt of atleast one polyhydric alcohol-modified polyamide, said polyhydricalcohol-modified polyamide comprising an amount of at least 0.1% wt andat most 10% wt, based on the total weight of the polyhydricalcohol-modified polyamide, of polyhydric alcohol residues chemicallybonded at least to a part of the polyhydric alcohol-modified polyamide,wherein said polyhydric alcohol is an organic compound containing threeor more hydroxyl groups in the molecule and is selected fromdipentaerythritol and tripentaerythritol; from 15 to 50% wt of at leastone filler comprising glass fibers; from 3 to 6% wt of at least oneimpact modifying rubber comprising ethylene amorphous copolymers graftedwith maleic anhydride; and from 0.01 to 3% wt of at least onecopper-containing stabilizer, wherein the copper-containing stabilizerprovides 75 to 150 ppm copper to the filled polyamide composition,wherein the polyamide is polyamide 6,6.
 2. The composition of claim 1,wherein the polyhydric alcohol-modified polyamide is obtained bycondensation reaction in the presence of the at least one polyhydricalcohol, of a monomer mixture of adipic acid and 1,6-diaminohexane;wherein the amount of polyhydric alcohol used in the condensationreaction is from 0.15 to 20% wt, based on the total weight of the atleast one monomer mixture.
 3. The composition of claim 1, wherein thepolyhydric alcohol-modified polyamide has a content of chemically bondedpolyhydric alcohol residues of at least 0.5% wt, and at most 10% wt,based on the total weight of the polyhydric alcohol-modified polyamide.4. The composition of claim 1, wherein the polyhydric alcohol-modifiedpolyamide comprises non-chemically bonded polyhydric alcohol in anamount of less than 2% wt, based on the total weight of the polyhydricalcohol-modified polyamide.
 5. The composition of claim 1, wherein thecopper-containing stabilizer comprises a copper compound and an alkalimetal halide in a weight ratio of copper compound:alkali metal halide offrom 1:99 to 30:70.
 6. The composition of claim 1, further comprising aco-stabilizer selected from the group consisting of hindered aminecompounds, hindered phenol compounds, and phosphorous compounds.
 7. Amethod of making the composition according to claim 1, said methodcomprising melt-blending the polyhydric alcohol-modified polyamide, thefiller, the rubber, the copper-containing stabilizer, and of any otheroptional ingredient.
 8. A method for manufacturing an article,comprising shaping the composition of claim 1 by a shaping techniqueselected from the group consisting of extrusion, injection moulding,thermoform moulding, compression moulding and blow moulding.
 9. Themethod according to claim 8, wherein the article is selected from thegroup consisting of films, laminates, automotive parts, engine parts,electrical parts, and electronics parts.
 10. The method according toclaim 8, wherein the article is suitable for high temperatureapplications.
 11. The composition of claim 3, wherein the polyhydricalcohol-modified polyamide comprises from 0.75% wt to 7% wt chemicallybonded polyhydric alcohol residues, based on the total weight of thepolyhydric alcohol-modified polyamide.
 12. The composition of claim 4,wherein the polyhydric alcohol-modified polyamide comprises less than1.5% wt non-chemically bonded polyhydric alcohol, based on the totalweight of the polyhydric alcohol-modified polyamide.
 13. The compositionclaim 5, wherein the weight ratio of copper compound:alkali metal halideis from 5:95 to 20:80.